Review request: 8049303: Transient network problems cause JMX thread to fail silenty

[Poonam Bajaj]

Hi Jaroslav,

On 8/26/2014 4:06 PM, Jaroslav Bachorik wrote:
> Hi Poonam,
>
> On 08/26/2014 12:27 PM, Poonam Bajaj wrote:
>> Sending the review request to serviceability-dev list as well...
>> -----------
>>
>> Could I have reviews for this change:
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8049303
>> Webrev: http://cr.openjdk.java.net/~poonam/8049303/webrev.00/
>
> L1499-1504 can be completely removed. They serve no purpose now.
>
Removed this piece of code.

> Please, adjust the indentation to fit the original one.

Corrected the indentation.

Updated webrev: http://cr.openjdk.java.net/~poonam/8049303/webrev.01/

Thanks,
Poonam

>
> Thanks,
>
> -JB-
>
>>
>> Problem and fix:
>> By default the JMX client side notification fetch timeout
>> (jmx.remote.x.notification.fetch.timeout) is 1 minute and the default
>> server connection timeout (jmx.remote.x.server.connection.timeout) is 2
>> minutes.
>>
>> If the client side connector thread makes a notification fetch request
>> to the server, but a transient network problem prevents the server
>> response from reaching the client, the client side connector will wait
>> for a response until the timeout period (1 minute) has expired before
>> throwing an IOException.
>>
>> The client side RMIConnector implementation handles the IOException, by
>> re-checking the connection status to understand whether or not it is
>> broken. If the connection is not available at that moment, the connector
>> fails by re-throwing the initial IOException. The problem is that this
>> re-check of the connection passes because the server side of the
>> connection doesn't time out until 2 minutes has passed (by default), so
>> the NotifFetcher thread
>> dies without posting a failed notification, and the client application
>> does not get a chance to recover.
>>
>> The fix is to forward the exception on the JMX client side before
>> checking the connection status.
>>
>> Testing:
>> All the jdk_jmx and jdk_management regression tests passed.
>>
>> The fix applies cleanly to 8u and 7u repos.
>>
>>
>> Thanks,
>> Poonam
>>
>>
>